Turn the oven to 180 degrees Celsius.
Line an ovenproof dish (the size of a dinner plate) with vegan margarine.
Unroll the thawed puff pastry sheet and roll flat to fit the size of the dish.
Cut the pastry into the shape of the dish.
Place the pastry inside the dish and set aside.
Make a thick custard filling: Mix all the custard ingredients together in a pot and bring to a simmer, stirring constantly until thick.
Cool slightly, pour the filling into the base and bake at 180 degrees Celsius for 30 – 40 minutes.
Remove from oven and chill in the fridge to set.
Sprinkle with cinnamon